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MeasureItemEventArgs.Graphics Property

Gets the Graphics object to measure against.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public Graphics Graphics { get; }

Property Value

Type: System.Drawing.Graphics
The Graphics object to use to determine the scale of the item you are drawing.

You use a Graphics object to determine the scale to use when setting the ItemHeight and ItemWidth. Different types of graphics objects can have different scales, such as the difference in measurement scale between a monitor screen and a printer.

The following code example demonstrates how to use the Graphics property to perform custom drawing of the items in a ListBox.

   public class Form1 : System.Windows.Forms.Form
   {
      private System.Windows.Forms.ListBox listBox1;
      private System.ComponentModel.Container components = null;


      protected override void Dispose(bool disposing)
      {
         if( disposing )
         {
            if ( components != null ) 
               components.Dispose();

            if ( foreColorBrush != null )
               foreColorBrush.Dispose();
         }
         base.Dispose(disposing);
      }

		#region Windows Form Designer generated code
      /// <summary> 
      /// Required method for Designer support - do not modify 
      /// the contents of this method with the code editor. 
      /// </summary> 
      private void InitializeComponent()
      {
         this.listBox1 = new System.Windows.Forms.ListBox();
         this.SuspendLayout();
         //  
         // listBox1 
         //  
         this.listBox1.DrawMode = System.Windows.Forms.DrawMode.OwnerDrawVariable;
         this.listBox1.Location = new System.Drawing.Point(16, 48);
         this.listBox1.Name = "listBox1";
         this.listBox1.SelectionMode = System.Windows.Forms.SelectionMode.MultiExtended;
         this.listBox1.Size = new System.Drawing.Size(256, 134);
         this.listBox1.TabIndex = 0;
         this.listBox1.MeasureItem += new System.Windows.Forms.MeasureItemEventHandler(this.listBox1_MeasureItem);
         this.listBox1.DrawItem += new System.Windows.Forms.DrawItemEventHandler(this.listBox1_DrawItem);
         //  
         // Form1 
         //  
         this.ClientSize = new System.Drawing.Size(292, 273);
         this.Controls.AddRange(new System.Windows.Forms.Control[] {
                                                                      this.listBox1});
         this.Name = "Form1";
         this.Text = "Form1";
         this.ResumeLayout(false);

      }
		#endregion

      [STAThread]
      static void Main() 
      {
         Application.Run(new Form1());
      }

      private void listBox1_MeasureItem(object sender, System.Windows.Forms.MeasureItemEventArgs e)
      {
         Font font = ((ListBoxFontItem)listBox1.Items[e.Index]).Font;
         SizeF stringSize = e.Graphics.MeasureString(font.Name, font);

         // Set the height and width of the item
         e.ItemHeight = (int)stringSize.Height;
         e.ItemWidth = (int)stringSize.Width;
      }

      // For efficiency, cache the brush to use for drawing. 
      private SolidBrush foreColorBrush;

      private void listBox1_DrawItem(object sender, System.Windows.Forms.DrawItemEventArgs e)
      {
         Brush brush;

         // Create the brush using the ForeColor specified by the DrawItemEventArgs 
         if ( foreColorBrush == null )
            foreColorBrush = new SolidBrush(e.ForeColor);
         else if ( foreColorBrush.Color != e.ForeColor )
         {
            // The control's ForeColor has changed, so dispose of the cached brush and 
            // create a new one.
            foreColorBrush.Dispose();
            foreColorBrush = new SolidBrush(e.ForeColor);
         }

         // Select the appropriate brush depending on if the item is selected. 
         // Since State can be a combinateion (bit-flag) of enum values, you can't use 
         // "==" to compare them.
         if ( (e.State & DrawItemState.Selected) == DrawItemState.Selected )
            brush = SystemBrushes.HighlightText;
         else
            brush = foreColorBrush;

         // Perform the painting.
         Font font = ((ListBoxFontItem)listBox1.Items[e.Index]).Font;
         e.DrawBackground();
         e.Graphics.DrawString(font.Name, font, brush, e.Bounds);
         e.DrawFocusRectangle();
      }

      /// <summary> 
      ///  A wrapper class for use with storing Fonts in a ListBox.  Since ListBox uses the 
      ///  ToString() of its items for the text it displays, this class is needed to return 
      ///  the name of the font, rather than its ToString() value. 
      /// </summary> 
      public class ListBoxFontItem 
      {
         public Font Font;

         public ListBoxFontItem(Font f) 
         {
            Font = f;
         }

         public override string ToString() 
         {
            return Font.Name;
         }
      }
   }

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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